package dome2;

import java.util.Stack;

public class MyQueue {
    private Stack<Integer> stack1;
    private Stack<Integer> stack2;
    public MyQueue() {
        stack1 = new Stack<>();
        stack2 = new Stack<>();
    }
    public void push(int x) {
        stack1.push(x);
    }
    public int pop() {
        if(stack2.isEmpty()) {
            if(stack1.isEmpty()) {
                return -1;
            }else {
                int size = stack1.size();
                for (int i = 0; i < size; i++) {
                    stack2.push(stack1.pop());
                }
            }
        }
        return stack2.pop();
    }
    public int peek() {
        if(stack2.isEmpty()) {
            if(stack1.isEmpty()) {
                return -1;
            }else {
                int size = stack1.size();
                for (int i = 0; i < size; i++) {
                    stack2.push(stack1.pop());
                }
            }
        }
        return stack2.peek();
    }
    public boolean empty() {
        return stack1.isEmpty() && stack2.isEmpty();
    }
}
